Update nonstandard.md

FitDiagnostics->MultiDimFit as fixed in 102x branch

docs/part3/nonstandard.md

@@ -223,7 +223,7 @@ The impact of a nuisance parameter (NP) θ on a parameter of interest (POI) μ i
 
 This is effectively a measure of the correlation between the NP and the POI, and is useful for determining which NPs have the largest effect on the POI uncertainty.
 
-It is possible to use the `FitDiagnostics` method of <span style="font-variant:small-caps;">Combine</span> with the option `--algo impact -P parameter` to calculate the impact of a particular nuisance parameter on the parameter(s) of interest. We will use the `combineTool.py` script to automate the fits (see the [`combineTool`](http://cms-analysis.github.io/HiggsAnalysis-CombinedLimit/#combine-tool) section to check out the tool.
+It is possible to use the `MultiDimFit` method of <span style="font-variant:small-caps;">Combine</span> with the option `--algo impact -P parameter` to calculate the impact of a particular nuisance parameter on the parameter(s) of interest. We will use the `combineTool.py` script to automate the fits (see the [`combineTool`](http://cms-analysis.github.io/HiggsAnalysis-CombinedLimit/#combine-tool) section to check out the tool.
 
 We will use an example workspace from the [$H\rightarrow\tau\tau$ datacard](https://github.com/cms-analysis/HiggsAnalysis-CombinedLimit/blob/main/data/tutorials/htt/125/htt_tt.txt),